Yields fall as investors seek safety

US Treasury yields fell to their lowest levels in weeks on Wednesday in a flight to safety that also helped lift gold to a three-month peak amid political risks in Europe and worries over US President Donald Trump's policies.

Political concerns, including a strong showing by far-right candidate Marine Le Pen in France's presidential race, sent a wave of overseas buyers to Treasuries, which offer a sizeable yield premium over government bonds from countries in Europe.

"Across the developed world the US is still pretty much the high-yielding choice and I would argue the US economy is by far the strongest of those choices," said Dominic Pappalardo, director of the taxable portfolio management team at McDonnell Investment Management in Oakbrook, Illinois.

"If you're in much of Europe or Asia where you have rates near zero as well as a tremendous amount of economic uncertainty, getting 2-1/2 per cent on your money is really, really attractive."

Yields on 7-, 10- and 30-year Treasuries fell to their lowest levels since mid-January, while 5-year note yields hit their lowest since Dec. 8.

Spot gold hit a three-month high of $US1,244.67 an ounce before paring gains slightly.

"There's underlying demand for gold as a hedge against political uncertainties on both sides of the Atlantic," said Ole Hanson, head of commodity strategy at Saxo Bank.

Even so, any corresponding US risk-off sentiment was little evident on Wall Street, where stocks ended mostly flat. Investors were digesting mixed earnings reports and the Dow Jones Industrial Average slipped as bank stocks weighed.

The Dow fell 35.95 points, or 0.18 per cent, to 20,054.34, the S&P 500 gained 1.59 points, or 0.07 per cent, to 2,294.67 and the Nasdaq Composite added 8.24 points, or 0.15 per cent, to 5,682.45.

Falling Treasury yields pushed down the dollar, which fell after two days of gains. Investors were also pricing out a March rate hike by the Federal Reserve amid uncertainty about Trump's protectionism and immigration policies.

The greenback declined 0.03 per cent against a basket of major currencies and the dollar index fell 0.23 per cent in late trading.

Oil prices gained slightly as investors covered short positions after a rise in US crude inventories was not as massive as many had feared, while gasoline futures jumped nearly 4 per cent after a surprise decline in fuel inventories.

US crude settled at $US52.34 a barrel, up 17 cents, or 0.33 per cent. Brent settled up 0.13 per cent, or 7 cents, at $US55.12.